Note 3 - Loans - Impaired Loan Balances by Portfolio Segment (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2022	Dec. 31, 2021
Recorded investment, with no related allowance recorded	$ 2,025	$ 2,232
Unpaid principal balance, with no related allowance recorded	2,025	2,233
Average recorded investment, with no related allowance recorded	2,209	2,520
Interest income recognized, with no related allowance recorded	7	69
Commercial Portfolio Segment [Member]
Recorded investment, with no related allowance recorded	0	0
Unpaid principal balance, with no related allowance recorded	0	0
Average recorded investment, with no related allowance recorded	0	4
Interest income recognized, with no related allowance recorded	0	0
Recorded investment, with a related allowance recorded	10	14
Unpaid principal balance, with a related allowance recorded	2	7
Related allowance	2	7
Average recorded investment, with a related allowance recorded	12	25
Interest income recognized, with a related allowance recorded	0	1
Recorded investment	10	14
Unpaid principal balance	2	7
Average recorded investment	12	29
Interest income recognized	0	1
Commercial Real Estate Portfolio Segment [Member] \| Construction and Land Development [Member]
Recorded investment, with no related allowance recorded	0	0
Unpaid principal balance, with no related allowance recorded	0	0
Average recorded investment, with no related allowance recorded	0	0
Interest income recognized, with no related allowance recorded	0	0
Recorded investment, with a related allowance recorded	0	0
Unpaid principal balance, with a related allowance recorded	0	0
Related allowance	0
Average recorded investment, with a related allowance recorded	0	0
Interest income recognized, with a related allowance recorded	0	0
Recorded investment	0	0
Unpaid principal balance	0	0
Average recorded investment	0	0
Interest income recognized	0	0
Commercial Real Estate Portfolio Segment [Member] \| Owner Occupied Commercial Real Estate [Member]
Recorded investment, with no related allowance recorded	0	8
Unpaid principal balance, with no related allowance recorded	0	5
Average recorded investment, with no related allowance recorded	8	71
Interest income recognized, with no related allowance recorded	0	1
Recorded investment, with a related allowance recorded	0	0
Unpaid principal balance, with a related allowance recorded	0	0
Related allowance	0
Average recorded investment, with a related allowance recorded	0	0
Interest income recognized, with a related allowance recorded	0	0
Recorded investment	0	8
Unpaid principal balance	0	5
Average recorded investment	8	71
Interest income recognized	0	1
Commercial Real Estate Portfolio Segment [Member] \| Non-owner Occupied Commercial Real Estate [Member]
Recorded investment, with no related allowance recorded	1,159	1,185
Unpaid principal balance, with no related allowance recorded	1,160	1,186
Average recorded investment, with no related allowance recorded	1,172	1,107
Interest income recognized, with no related allowance recorded	1	23
Recorded investment, with a related allowance recorded	0	0
Unpaid principal balance, with a related allowance recorded	0	0
Related allowance	0
Average recorded investment, with a related allowance recorded	0	30
Interest income recognized, with a related allowance recorded	0	0
Recorded investment	1,159	1,185
Unpaid principal balance	1,160	1,186
Average recorded investment	1,172	1,137
Interest income recognized	1	23
Residential Portfolio Segment [Member] \| Residential [Member]
Recorded investment, with no related allowance recorded	852	1,021
Unpaid principal balance, with no related allowance recorded	859	1,031
Average recorded investment, with no related allowance recorded	1,013	1,217
Interest income recognized, with no related allowance recorded	6	41
Recorded investment, with a related allowance recorded	0	0
Unpaid principal balance, with a related allowance recorded	0	0
Related allowance	0	0
Average recorded investment, with a related allowance recorded	0	61
Interest income recognized, with a related allowance recorded	0	2
Recorded investment	852	1,021
Unpaid principal balance	859	1,031
Average recorded investment	1,013	1,278
Interest income recognized	6	43
Residential Portfolio Segment [Member] \| Home Equity Line of Credit [Member]
Recorded investment, with no related allowance recorded	4	4
Unpaid principal balance, with no related allowance recorded	4	4
Average recorded investment, with no related allowance recorded	4	5
Interest income recognized, with no related allowance recorded	0	1
Recorded investment, with a related allowance recorded	0	0
Unpaid principal balance, with a related allowance recorded	0	0
Related allowance	0
Average recorded investment, with a related allowance recorded	0	0
Interest income recognized, with a related allowance recorded	0	0
Recorded investment	4	4
Unpaid principal balance	4	4
Average recorded investment	4	5
Interest income recognized	0	1
Consumer Portfolio Segment [Member]
Recorded investment, with no related allowance recorded	0	0
Unpaid principal balance, with no related allowance recorded	0	0
Average recorded investment, with no related allowance recorded	0	0
Interest income recognized, with no related allowance recorded	0	0
Recorded investment, with a related allowance recorded	0	0
Unpaid principal balance, with a related allowance recorded	0	0
Related allowance	0
Average recorded investment, with a related allowance recorded	0	0
Interest income recognized, with a related allowance recorded	0	0
Recorded investment	0	0
Unpaid principal balance	0	0
Average recorded investment	0	0
Interest income recognized	$ 0	$ 0

Average amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (c)(1)
-URI https://asc.fasb.org/extlink&oid=123577603&loc=d3e5212-111524

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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-Section 50
-Paragraph 17
-URI https://asc.fasb.org/extlink&oid=123577603&loc=d3e5258-111524

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